1. Field of the Invention
This invention relates to a self-rechargeable portable telephone, and more particularly to a self-rechargeable portable telephone/handset having a power generation device capable of converting mechanical energy resulting from movement of the telephone into electric energy and storing the electric energy in a battery cell.
In a preferred embodiment of the invention, the power generation device of the portable electric telephone includes a power generation device of the type described in copending parent U.S. patent application Ser. No. 10/170,717, including a fixed or movable coil, a corresponding movable or fixed magnet structure, a rectifier, and at least one of the following additional features:                A. The magnet structure including a series of N-S-N-S poles constructed using a novel joining method that overcomes problems of high remanance and coercivity, and thereby increases flux density;        B. The stationary or movable coil including windings constructed using a novel winding method that results in maximum magnetic lines cutting in linear motion.        
2. Description of Related Art
Typically, portable telephones used for wired and wireless communications employ a disposal non-rechargeable primary cell or a rechargeable secondary cell that must be recharged through an external charging device.
In copending U.S. patent application Ser. No. 10/170,717, it was proposed to provide a portable telephone having an internal generator arranged to provide charging current to a secondary cell upon movement of the telephone, thereby enabling the use of environmentally-friendly secondary cells without the need for an external charging device. In addition to eliminating the inconvenience of battery. disposal or charging, the proposed portable telephone offered advantages of energy conservation and pollution reduction due to elimination of the need to draw charging power from the public power grid.
Although showing great promise, a problem with implementation of the self-rechargeable telephone has been the relatively low magnetic efficiency of suitable sized and priced magnets and coils, which typically have a relatively low flux density and/or provide an inefficient distribution of magnetic lines. Although more efficient magnets or magnet structures are known, such as the rare earth magnets disclosed in U.S. Pat. Nos. 5,347,186 and 5,818,132; the composite armature and multiple coil structure of U.S. Pat. No. 4,500,827; the wound magnetic core disclosed in U.S. Pat. No. 4,709,176; or the composite coil and stack neodymium disc magnets disclosed in U.S. Pat. No. 5,975,714, they are generally expensive to manufacture and/or too large for the applications mentioned above. Further, while distribution of magnetic lines from a coil can be improved by adding a permeable material to the coil structure, the permeable material has the disadvantage not only of adding to the complexity of the structure, but also to the diamagnetic resistance effect.